Abrading device



Feb. 2, 1960 L. s. SlMJlAN 7 2,923,100

ABRADING DEVICE Filed Oct. 11, 1957 r 2,923,100 ABRADING DEVICE Luther G. Simjian, Greenwich, Conn., assignor to Reflectone Electronics, Inc., Stamford, Conn., a corporation of Connecticut I Application October 11,1957, Serial No. 689,569 12' Claims. (Cl. 51'7) This invention relates to abrading and polishing of thus causing abrasive action.

One of the major difiiculties in polishing irregular articles lies in the necessity of bringing abrasive materials in contact with the irregular contours, For this reason, many irregular articles must be polished by hand without the use of the usual motor-operated'buffing or abradingwheels. The present invention overcomes these ditficulties by using a fluent abrasive or polishing mixture,

which'can be rigidified about the article to be polished. The mixture is housed in a receptacle and the object to be polished is immersed into the mixture when the mixture is fluent. Next, the mixture is rigidified about the article and relative motion is introduced between the rigidified mixture and the article to cause abrading of the irregular contour surfaces of thearticles. l

The mixtureempl'oyed may comprise small abrasive particles such .as Carborundum, boron carbide, silicon carbide, aluminum oxide, diamond powder, etc. or when using a magnetic field for effecting rigidification of the mixture, the mixture may comprise abrasive magnetic particles such as Alnico, hardened steel particles, barium ferrites, manganese-bismuth particles, or as an alternate the mixture may be a mix of abrasive nonmagnetic particles and of abrasive magnetic particles in suitable proportions. Still further, the abrasive mixture may be mixed with a suitable amount of liquid such as oil, water, oi ka cleaningfluidlsuch as turpentine, carbon tetrachloride, trichlo-rethylene, etc. in order to prevent coagulation of the particles and to enhance the finish of the surface tojjbe abraded. v g r One 'of the objects 'of this invention therefore isto provide a polishing arrangement which avoids one or more of the disadvantages and limitations of the prior art arrangements; I p e Another object of the invention is to polish or abrade objects without resorting to manual manipulation;

" Another object ,of the invention is to abrade the surface of irregular objects for the removal of scale, dirt, paint,

"Another object of the invention is to provide an arrangement which is suitable for treating simultaneously a plurality of articles; T

Anotherandfurther object of theinvention is the provision of an apparatus adapted for polishing articles on a mass production basis.

The invention will be b'etterunderstood from the folments, reference being made to' the'accompanying draw ing in which:

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2,923,100 Patented Feb.- 2, 1960 ice . 2 Figure 1 is a side elevational view of a typical ap'paratus embodying one form of the invention;

Figure 2is an end elevational view of Figure 1;

Figure 3 is a side elevational view, partly in section, of an alternate apparatus embodying one form of the invention;

Figure 4 is an end view of an alternate arrangement which may be used in conjunction with the apparatus of.

12 and 13. A drum or barrel 14 equipped with shafts. 15 and 16 is supported for rotation in brackets 12 and 13 in the usual manner by the use of sleeve or ball bearings 1 (not shown). An electric motor 17 is adapted to rotate the barrel 14 via a belt drive 18 and pulley 19 which is fastened to shaft 16. The barrel or drum which is de picted as being octagonal in shape but which may be also of hexagonal shape or of any other suitable configuration,-

contains a plurality of articles to be abraded, such as articles 20 which are surrounded by asuitable abrasive mixture 21. A typical method of supporting the articles Within the mixture is illustrated in Figure 6 wherein a flexible cable,

rope, or wire 22 traverses the length of the barrel andv objects 20, for instance a spur gear, and spacer 23 alternately are placed thereon. It Will be observed that by virtue of employing a rope or wire 22, the articles are not mounted rigidly within the drum but may oscillate and vibrate, depending upon the motion imparted to barrel 14. The spacers 23 serve to space the objects to be abraded from one another in order to avoid damaging the objects by their abrading one another.

The suspending means 22 together with the object to.

be abraded are placed into the barrel by means of a suitable opening and cover 25 in the drum and after the I articles have been placed into the drum, the drum. may

be filled with the abrasive mixture through a suitable top funnel and opening 26 inthe drum in such a manner that the abrasive mixture surrounds the object to be abraded. For the general character and type of the abrasive mixture, reference is made to one of the previousparagraphs.

. Disposed on the outside of the drum there is arranged a plurality of electromagnetic pole pieces,'numerals 30? and 31 which are held to the drum by means of supporting brackets 32. The magnetic pole pieces are equipped with magnetic windings 33 and 34 respectively which may be energized from a power supply 35 via suitable electrical conductors and electrical contact brushes together with a set of slip rings 36 fastened to shaft 15. By virtue of this arrangement, the magnets will rotate in' unison with the drum whenever rotation is imparted to the drum I the drum and the drum is filled with the abrasive mixture,

which in this instance is a magnetizable abrasive mixture,

power supply 35 is energized to establish an electromagnetic field to the mixture confined within the drum. The

magnetic field causes the, mixture to rigidity and when energizing motor 17 for imparting to the drum bodilydisplacement in the form of rotation, relative motion between the rigidified magnetic mixture and the articles suspended therein isobtained. It will be noted that the degree of rigidity imparted to the mixture must be such that the abrasive mixture becomes a united mass which constrains the objectsyet does not grip the objects in such a tight manner that the object to be abraded and the mixture would lack relative motion therebetween. This adjustment can be made best by regulating the current flow through the windings 33 and 34 in sucha manner that the rigidity of the mixture is maintained somewhat below the maximum rigidity possible.- In this manner, vibration of the drum obtained as a result of being rotated is transmitted to the rigidified mixture and also to the suspended articles. Since the articles and the rigidified mixture have a differing mass and as the articles are suspended loosely so as to allow slight motion,'relative motion between the mixture and the articles is attained.

An alternate design is shown in Figure 4 wherein the drum 14 is surrounded bya plurality ofstationary pole pieces 41- which are equipped with amagnet winding'42, It will be observed that the magnetic fluxagain will penetrate the barrel and rigidity themixture therein. By arranging the pole pieces in proximity to one another and providing a suflicient number of ampere-turns, a substantially constant flux pattern within the mixture can be obtained and the-overall effect is the same as the one described in connection with Figure 1.

For best results it will be apparent that the barrel or drum should be made of nonmagnetic material in orderabraded. It should be noted that thesuspension means- 22 and spacing means 23 (Figure 6) may be eliminated if the articles to be abraded are immersed into the mixture, such as an operator placing the objects into the mixture and avoiding articles to be abraded touching one another. As a next step the mixture is rigidified and the articles will be retained very much alike to a mold surrounding a cast object. When imparting vibration to the apparatus, the object will move relative to the surrounding mixture.

Figure 3 shows still another embodiment of the invention using a slightly different apparatus for obtaining the same or similar results. A receptacle 50 having an opening with lid 51 is mounted on a plate 52 by means of brackets 53 and 54. The receptacle is equipped with a magnetic pole piece 55 and winding 56. The pole piece may be either attached to the receptacle or may be stationary with respect to the receptacle when motion is imparted to the receptacle. The receptacle may be agitated by an electric motor 57 fastened to a base plate 58 and driving receptacle 50 via an eccentric cam 59 and spring combination 60. In order that the container 50 vibrate, plates 52 and 58 supporting respectively the receptacle and motor are pivotally mounted with respect to one another at hinge 61. This arrangement vibrating the receptacle, 50 may be considered similar to conventional shakers and vibrators, such as are employed for mixing commercial paints, etc.

Figure shows still another slight variation of the apparatus shown and described in connection with Figure 1. Magnetic pole pieces 71 are disposed at the inside of the drum 70 instead of being supported on the outside of electric current withrespect to time whichmay be; ap pl edt the, gqe mfiq ns ad ai ta ning-t e: electric current flow,constantwith-respeghto time; as thereceptacle vib rates, the current flow may be cyclically changed with respect to the-motionof thearticle sothat 4 as the article is accelerated in the upward or downward direction, the magnetic mixture-fora brief periodis made less rigid and shortly thereafter more rigid in order to cause impact of the article on the again rigidified mixture. It will be noted that in this event the variations of the electric field must be synchronized with the motion of the container and the objecttherein.

Although magneticrneans are employed for rigidifying the abrasive mixture described in connection with Figures 1, 3 and 5, it shall be clearly understood that other means for; rigidifying the mixture; may beemployed; such as changing the configuration of the receptacle shown in my copending application for US, Letters Patent, Serial No. 654,283 filed April 22; 1957; now abandoned; The mixture may then be composedof nonmagnetic particles.

It will be apparent to those skilled in the art that most favorable results are achieved when the articles to be abraded are substantially nonmagnetic whileemploying a magnetizable mixture and an electromagnetic field coupled thereto. Conversely, magnetizable objects may be abraded advantageously in a mixture which'is rigidified by other than magnetic means. Furthermore, permanent magnetic means may be substituted for electromagnets without departing from the principle of the invention.

While there have been described certain embodiments of the foregoing invention, it will be apparent to those skilled in the art that various modifications and' changes. may be made therein without departing from the spirit of. the invention which shall be limited only by the scope of the appended claims.

What is claimed is: p

1'. A method of abrading the contours of anarticle comprising the steps of inserting the article to be abraded in a receptacle containing anabrasive mixture when the, mixture is substantially fluent whereby the, mixture, is caused to surround the contoursto be abraded; applying to the mixture a magnetic field which rigidifies the mixtureand renders it sutficiently rigid to contrain the article.

yet. permitting limited, motion, of the article relative to, the mixture, and bodily displacing the article and mixture; by applying motion to the receptacle and the relative motion between the article and mixture causingabrading of the article.

2. Amethod of abrading the contours of an article, comprising the steps of inserting the-article to be abraded ina receptacle containing a magnetizable abrasive mixture when the mixture is substantially fluent whereby the mixture is caused to surround thecontours to be abraded;

applying to the mixture, a magnetic field which rigidifies. the mixture and renders it sufficiently rigid to constrain. the article yet permitting limited motion of the article relative to the rigidified mixture, and bodily displacing the-article and mixture by applyingnmotion to the receptacle and the resulting relative motionbetween the article andmixture causing abrading of the article.

3. A method of abrading the contours of an article 7 and mixture by applying motion to the receptacle and,

the relative motion between the-article andmixturecausingabrading of the article.

4. A method of abrading the contours of aplurality of articles comprising the steps of loosely supporting the articles to, be abradedin a receptacle containinga mag netizable abrasive mixture when themixtureissubstati-r tially fluent whereby the mixtureis caused: to surround the contoursof the articles'to beabraded; applying; to: thernixturea magnetic field whichrigidifies.themizitl re.

and renders it sufficiently rigid to constrain said articles yet permitting limited motion of each article relative to the rigidified mixture, and bodily displacing the articles and mixture by applying motion to the receptacle and the resulting relative motion between each article and the surrounding mixture causing abrading of the articles.

5. A method of abrading the contours of a plurality of articles comprising the steps of loosely supporting the articles to be abraded in a receptacle containing a magnetizable abrasive mixture when the mixture is substantially fluent whereby the mixture is caused to surround the contours of the articles to be abraded; applying to the mixture a magnetic field which rigidifies the mixture and renders the mixture sufficiently rigid to constrain the articles yet permitting limited motion of the articles relative to the rigidified mixture, and bodily displacing the articles and mixture within the magnetic field by applying motion to the receptacle and the resulting relative motion between each article and the surrounding mixture causing abrading of the articles.

6. A method of abrading the contours of a plurality of articles comprising the steps of inserting the articles to be abraded in spaced relationship in a receptacle containing a magnetizable abrasive mixture when the mixture is substantially fluent whereby the mixture is caused to surround the contours of the articles to be abraded; applying to the mixture a magnetic field which rigidifies the mixture and renders the mixture sufliciently rigid to constrain the articles yet permitting limited motion of the articles relative to the rigidified surrounding mixture, and bodily displacing the plurality of articles and mixture within the magnetic field by applying motion to the receptacle and the resulting relative motion between each article and the rigidified mixture causing abrading of the respective article contours.

7. Apparatus of the character described comprising: a receptacle; a magnetizable abrasive mixture in said receptacle in which an article to be abraded may be immersed; magnetic means disposed to rigidity the mixture about the article yet permitting limited motion of the article relative to the mixture, and means bodily displacing the receptacle and article by imparting motion to the receptacle while the mixture is rigidified.

8. Apparatus of the character described comprising: a receptacle; a magnetizable abrasive mixture in said receptacle in which an article to be abraded may be immersed; electromagnetic means disposed to coact with 6 the mixture to rigidity it about the article yet permitting limited motion of the article relative to the rigidified mixture, and means bodly displacing the receptacle and article by imparting motion to the receptacle while the mixture is rigidified and this motion causing abrading of the article. a

9. Apparatus as set forth in claim 8 wherein the electromagnetic means are exterior of the receptacle.

10. Apparatus as set forth in claim 8 wherein the electromagnetic means are disposed at the inside of the receptacle.

11. Apparatus of the character described comprising: a receptacle; a magnetizable abrasive substantially fluent mixture in said receptacle in which an article to be abraded may be immersed; mounting means fastened to the receptacle for loosely supporting the article thereon whereby the article is in contact with the mixture; means disposed to produce a magnetic flux which rigidifies the mixture to render it sufliciently rigid to constrain the article yet permitting limited motion of the article relative to the mixture, and means bodily displacing the article and mixture by applying motion to the receptacle and the relative motion between the article and mixture causing abrading of the article.

12. Apparatus of the character described comprising: a receptacle; a magnetizable abrasive substantially fluent mixture in said receptacle in which a plurality of articles to be abraded may be immersed; mounting means fastened to the receptacle for loosely supporting the articles in spaced relationship whereby the articles are in contact with the mixture; electromagnetic means disposed to produce a magnetic flux which rigidifies the mixture to render it sufiicientl-y rigid to constrain each of said articles yet permitting limited motion of each article relative to the rigidified mixture, and means bodily displacing the plurality of articles and mixture by applying motion to the receptacle and the relative motion between said articles and mixture causing abrading of said articles.

References Cited in the file of this patent UNITED STATES PATENTS 

